The present invention pertains to a compressible sealing ring, and in particular, to a compressible sealing ring which functions as a pressure sensor.
Fluid seals are made of a variety of materials and have a multitude of design configurations that include, but are not limited to, (i) a circular conformable elastomer O-ring seated in a channel (gland) of a metallic or plastic fitting, (ii) circular washer made of soft conformable metallic or plastic material, (iii) flat gasket of various flat patterns made with conformable fibrous, cellulous, particulate, or polymeric material, (iv) circular compression fittings with off-set tapered mating surfaces, (v) circular flared fittings with conformable flared tubings, and (vi) circular threaded pipe fittings with off-set tapers, etc.
It is known that sealing using conformable materials is achieved when such material is placed between relatively rigid mating surfaces and that sealing occurs when the material is put under pressure and displaces to conform to and fill the space between the mating surfaces.
It is also known that sealing of relatively rigid mating surfaces is achieved when such surfaces are in full or partial and often tight contact. Examples of such sealing are compression fittings and threaded pipefittings that often have tapered mating surfaces that are offset to create tight contact during rotational tightening.
It would be advantageous, however, to be able to determine the pressure that the seal is under, and in particular, to determine any pressure variance around the course of the seal. This could be used to determine if the seal member is unseated, seated properly and evenly, and tightened under the appropriate torque. In addition, it would be advantageous to be able to sense the contained fluid pressure being exerted onto the seal to ascertain if a leak path has been initiated therethrough.
Most pressure sensors, however, function by converting mechanical movement of a diaphragm to an electrical change in resistance or capacitance. This is achieved through the use of active materials like piezo film. However, such sensors are fairly costly, and in addition, it would be difficult to use such sensors to determine if a seal is under uniform pressure and seated properly. Accordingly, it is an object of the present invention to provide a seal member having both sealing and sensing functionality that is capable of sealing and determining if the seal is under proper compression or torque load, and that is also capable of sensing contained fluid pressure and pressure variation indicating leakage across the sealing member.